There are a number of inventions which use the attic of a building as a source for solar heated air, or water or the like. A discussion of the usefulness of devices which convey the heat energy to places remote from the attic is well covered in 1985, U.S. Pat. No. 4,502,467 by Smith, and in 1981, U.S. Pat. No. 4,242,872 by Shaw, and in 1980, U.S. Pat. No. 4,241,725 by Emon et al. I have given a thorough coverage of the subject in my 1991, U.S. Pat. No. 5,014,770. It has been a major objective of these and other similar inventions to remove heat energy from the attic in the most efficient manner and with the lowest capital investment, and to minimize the cost of extracting the heat energy from the roof of a building. However, all of the above inventions are not completely self-sufficient. They require an electricity source, generally provided by a local community power plant and produced by burning fossil fuel.
Self-sufficient solar energy converting devices have been invented such as photovoltaic cell arrays and thermosyphon solar-energy-to-liquid heat exchanger panels. These may be mounted on roof tops, or in non-shaded open spaces. Windmills erected in high places are also used in some cases, but they tend to be less reliable. These devices are effective but are generally considered to be aesthetically objectionable. The non-traditional look of solar roof panels and efficient windmills has caused people to reject them for all but industrial areas. Recently, in many suburban areas, ordinances have been written to disallow the use of "in-view" solar panels and windmills. Even if these self-sufficient devices could be aesthetically improved, initial installation costs are prohibitively high and based on the present day relatively low cost of fossil fuel energy, they appear to be a poor investment.
A self sufficient attic-based solar heating system is especially needed for heating air and water of buildings which are in places where it is impractical to include electricity from a community power plant.